I've changed the settings, anti fast cycle from 5 to 10 mins (6 times an hour) and anti fast cycle flow temp from -6 to -10.
Interestingly, Honeywell T3R thermostat parameters has the following:
cycle rate : 1, 2, 3, 6, 9, 12
default is set to 6
Minimum on time: 1,2,3,4,5, 10, 15, 20, 25, 30...